Sand Beaches or Low Plains. The no action and relocation alternatives are applicable. Bulkheads
are generally inappropriate unless an elevated feature, such as a promenade or parking lot, is needed.
Vertical bulkheads induce toe scour and wave reflections, and could cause a total loss of the beach
fronting the bulkhead. Revetments are suited for protecting features directly behind the beach since they
absorb wave energy and are flexible if settlement occurs. However, they have an adverse aesthetic effect
on the beach, and can limit use or access to the shore. Their use by a single landowner is generally a
problem because they are subject to flanking. Breakwaters are also well suited because they trap and hold
sand moving both alongshore and on- or offshore. However, they can cause extensive downdrift erosion
damages and they are expensive to build. Groins can effectively build beaches on their updrift sides but
can also cause accelerated downdrift erosion. Their functional behavior is complex and difficult to
predict. Beach fills retain the natural form and character of the beach and enhance its recreational
potential. Local sources of suitable sand are not always available, however, and fills do require periodic
renourishment. Vegetation, effective in low wave-energy situations, has low initial costs and enhances
natural appearance. Unfortunately, foot and vehicular traffic damage plantings. Drainage controls and
slope flattening are not applicable to beach shorelines. Perched beaches are ideally suited as they
increase the available beach area. Combination methods are often excellent, such as a perched beach that
is further stabilized with vegetation.
Wetlands. Erosion control structures built near wetlands should be placed at a low bluff or beach
behind the marsh. For protection of the marsh itself, vegetation is the only appropriate alternative. To
assist establishment bf plantings, however, small temporary breakwaters may be required. Beach fills or
perched beaches may also be used to provide a suitable substrate for planting in some areas.
Applicability to Shoreline Uses
Some methods lend themselves more readily than others to particular shoreline uses. It is
important to choose a method that performs its function without interfering with planned shoreline uses -
No action obviously does not enhance use of the shoreline, although continued erosion may have an
adverse impact. Relocation involves similar considerations. Bulkheads create an access problem unless
stairs are provided. Vertical structures also cause wave reflections that can erode the remaining beach.
Bulkheads are necessary when a water depth for boating activities is needed at the shore. Revetments of
randomly placed, rough stone definitely hinder access to the beach. Smooth structures, such as concrete
blocks, cause less difficulty for walkers. Breakwaters provide an area sheltered from waves but also can
hinder circulation and cause water quality problems. Beaches built behind breakwaters have enhanced
recreational potential. Rough stone structures provide an improved habitat for certain fish species but
may be hazardous to climbers. High structures may also obstruct the view of the water and have an
undesirable aesthetic effect. Groins may hinder travel along the beach, but any sand trapped updrift from
groins improves beach conditions. Beach fills enhance recreational uses of the shore. Vegetation
improves the wildlife habitat but hinders other uses of the beach because traffic through the plantings
must be restricted. Drainage controls have little impact on shoreline uses. Slope flattening reduces
available land at the shore. Perched beaches provide increased beach area for recreation. Rubble sills
can serve as a habitat for certain fin and shellfish species. The sudden step off sheet pile sills can be
hazardous to bathers. Submerged sills can also hinder access for boaters and could pose a potential
hazard.
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